US7617710B2 - Roller leveller with variable center distance - Google Patents

Roller leveller with variable center distance Download PDF

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Publication number
US7617710B2
US7617710B2 US10/591,912 US59191205A US7617710B2 US 7617710 B2 US7617710 B2 US 7617710B2 US 59191205 A US59191205 A US 59191205A US 7617710 B2 US7617710 B2 US 7617710B2
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Prior art keywords
leveller
rolls
center
entry
roll
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Expired - Fee Related, expires
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US20070186607A1 (en
Inventor
Jacques-Yves Bourgon
Dominique Kircher
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ArcelorMittal France SA
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ArcelorMittal France SA
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D1/00—Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling
    • B21D1/02—Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom; Stretching sheet metal combined with rolling by rollers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
    • B21B2015/0071—Levelling the rolled product

Definitions

  • the present invention relates to a tensionless leveller intended for levelling a metal strip and to the levelling method using said leveller.
  • a metal strip or plate undergoes various operations, such as hot rolling and cold rolling, which are intended to give it uniform dimensions over its entire length.
  • a rolled metal strip has at any point a constant thickness and a constant width.
  • the rolling operation is insufficient for obtaining a defect-free strip. This is because it exhibits non-developable flatness defects, such as waviness at the edges or the center, and/or developable defects such as a curl or a crown, that is to say a curvature either along the length or along the width of the strip, respectively.
  • levelling the strip in a multi-roll leveller.
  • a leveller consists of two superposed cassettes each supporting several motor-driven rolls, of constant diameter, offset with respect to one another and placed alternately above and below the path of the strip.
  • This type of leveller is configured, in terms of the number of rolls, the diameter of the rolls, the center-to-center spacing and the setting, so as to achieve satisfactory levelling of the strip, the thickness of which lies within a defined range.
  • the center-to-center spacings of the rolls are constant and set so that the ratio of the roll diameter to the center-to-center spacing is between about 0.90 and about 0.95.
  • the levelling forces and moments are large.
  • manufacturers have developed levellers in which all of the center-to-center spacings are increased so that the ratio of the diameter to the center-to-center spacing is around 0.70 to 0.80.
  • this no longer allows the non-developable defects to be corrected over the entire range of the leveller in terms of strip thickness, and in particular on a thinner strip.
  • the object of the present invention is therefore to propose a leveller in which the levelling forces and moments are reduced compared with those of a conventional leveller, while still maintaining good flatness correction over the entire range of the leveller, and by making it easier to bring curl and crown under control.
  • the subject of the invention is a tensionless leveller intended for levelling a metal strip, having an entry and an exit, comprising n+1 rolls, of the type comprising two superposed cassettes each supporting at least n/2 motorized rolls of constant radius R, offset with respect to one another and placed alternately above and below the path of the strip, the axis of each of the rolls of one cassette being separated from the axis of the immediately successive roll of the other cassette by a center-to-center spacing E k , in which:
  • said leveller optionally including means for adjusting the center-to-center spacings E k .
  • the leveller according to the invention may furthermore have the following features:
  • the subject of the invention is also a method for levelling a metal strip, in particular a steel strip, in which this leveller is used with a degree of plastic deformation of at least 60% and at most 90%.
  • the invention consists in proposing a leveller in which at least the first five rolls starting from the entry of the leveller have a radius/center-to-center spacing ratio identical to that of conventional levellers, in which at least the last five rolls from the entry of the leveller have a radius/center-to-center spacing ratio close to that of a decurler, and in which the center-to-center spacing between the intermediate rolls of the leveller is advantageously increased.
  • FIG. 1 shows a schematic cross-sectional view of a tensionless multi-roll leveller according to the invention
  • FIG. 2 shows a calculation curve of the residual curl of a levelled metal strip as a function of the exit clamping of the leveller, for a degree of plastic deformation of 60%;
  • FIG. 3 shows a calculation curve of the residual curl of a levelled metal strip as a function of the exit clamping of the leveller, for a degree of plastic deformation of 80%.
  • FIG. 1 shows schematically a leveller 1 comprising a lower cassette 2 and an upper cassette 3 being two superposed cassettes 2 , 3 , each supporting motorized rolls 4 , 4 ′ of constant radius R.
  • this strip 5 is made to run between the rolls 4 , 4 ′ and a leveller entry, corresponding to the entry of the strip 5 into the leveller 1 , and a leveller exit, corresponding to the exit of the strip 5 from the leveller 1 , are thus defined.
  • the rolls 4 , 4 ′ are positioned so as to be offset one with respect to another and placed alternately above and below the path of the metal strip 5 .
  • each cassette 2 , 3 must support at least n/2 rolls 4 , 4 ′ and, more precisely, for a leveller 1 comprising n+1 rolls 4 , 4 ′, the lower cassette 2 comprises (n/2)+1 rolls 4 and the upper cassette 3 comprises n/2 rolls 4 ′.
  • the axis of each of the rolls 4 , 4 ′ of a given cassette 2 , 3 is separated from the axis of the immediately successive roll 4 , 4 ′ of the other cassette by a center-to-center spacing E k , which can be varied.
  • the center-to-center spacing E k may be varied using adjustment means (not shown).
  • the inventors have demonstrated by reducing the radius/center-to-center spacing ratio of the rolls down to a value of around 0.8, starting from the fifth roll from the entry of the leveller, in a leveller whose radius/center-to-center spacing ratio between at least the first five rolls from the entry of the leveller corresponds to the radius/center-to-center spacing ratio of a conventional leveller, the levelling forces and moments can be reduced by 5 to 25% depending on the type of adjustment made.
  • the R/E k ratio is equal to the ratio R/E 1 , in which E 1 corresponds to the center-to-center spacing between the first roll from the entry of the leveller and the second roll from the entry of the leveller, R/E 1 being between 0.90 and 0.95, limits inclusive, which values correspond to the radius/center-to-center spacing ratio of a conventional leveller.
  • the R/E k ratio is equal to the ratio R/E n , in which E n corresponds to the center-to-center spacing between the last roll from the entry of the leveller and the penultimate roll from the entry of the leveller, R/E n being between 0.70 and 0.80, limits inclusive, which values correspond to the radius/center-to-center spacing ratio of a conventional decurler.
  • the ratio R/E 1 is always greater than the ratio R/E n . Furthermore, it is also recommended that, between the fifth roll from the entry and the (n ⁇ 1)th roll from the entry of the leveller, that is to say when k varies from 5 to n ⁇ 1, the following relationships are satisfied: R/E n ⁇ R/E k ⁇ R/E 1 , and R/E k ⁇ R/E k+1 ,
  • the power of the leveller according to the invention will be 15 to 20% less than the power of a conventional leveller.
  • the inventors have observed an increase in the number of operating points using a leveller according to the invention, compared with a conventional leveller having the same number of rolls.
  • the number of operating points of a leveller is determined by the adjustment to be made to the leveller in order to obtain, on leaving the leveller, a strip having a zero curl and a zero crown.
  • the larger the number of operating points for a given leveller the lower the constraint as regards the adjustments. This therefore represents an additional advantage, since the time required to adjust the leveller according to the invention will be able to be reduced.
  • the R/E k ratio is essential for the R/E 1 ratio, to within the accuracy of setting the center-to-center spacing between the rolls, for at least the first five rolls from the entry of the leveller.
  • the leveller comprises more than nine rolls, that is to say n is equal to or greater than 8, in order for both non-developable defects and developable defects to be properly corrected. This is because, with fewer than nine rolls, it becomes difficult to bring the developable defects under control, and the metal strip may retain a residual crown and a residual curl.
  • the leveller comprises between 15 and 23 rolls (limits inclusive), i.e. 14 ⁇ n ⁇ 22.
  • the leveller advantageously comprises between 11 and 17 rolls, i.e. 10 ⁇ n ⁇ 16.
  • leveller Depending on the quality of resolution of the flatness defects and the desired reduction in levelling force and moment, the inventors have developed various types of leveller, which we will now describe.
  • the leveller is divided into two zones.
  • a first zone is thus between the first roll from the entry of the leveller and the (x+1)th roll from the entry of the leveller, that is to say when k varies from 1 to x, and extends at least as far as the fifth roll from the entry of the leveller.
  • the radius/center-to-center spacing ratio R/E k is constant and between 0.90 and 0.95 (limits inclusive).
  • the second zone lies between the (x+1)th roll from the entry of the leveller and the last roll from the entry of the leveller, which is the (n+1)th roll, that is to say when k varies from x+1 to n, and starts at least from the (n ⁇ 3)th roll from the entry of the leveller.
  • the radius/center-to-center spacing ratio R/E k is constant and between 0.70 and 0.80 (limits inclusive).
  • the leveller is divided into three zones.
  • a first zone lies, as in the first embodiment, between the first roll from the entry of the leveller and the (x+1)th roll from the entry of the leveller, that is to say when k varies from 1 to x, and extends at least as far as the fifth roll from the entry of the leveller.
  • the radius/center-to-center spacing ratio R/E k is constant and between 0.90 and 0.95 (limits inclusive).
  • R/E x a second zone in which one of the radius/center-to-center spacing ratios, which will be called R/E x , is between 0.80 and 0.90 (limits inclusive).
  • This second zone lies between the fifth roll from the entry of the leveller and the (n ⁇ 4)th roll from the entry of the leveller, that is to say when x varies from 5 to n ⁇ 4.
  • a third zone lies between the (x+1)th roll from the entry and the last roll of the leveller (the (n+1)th roll), that is to say when k varies from x+1 to n.
  • the radius/center-to-center spacing ratio R/E k is constant and between 0.70 and 0.80 (limits inclusive).
  • the leveller is again divided into three zones.
  • a first zone lies, as in the previous embodiments, between the first roll from the entry of the leveller and the (x+1)th roll from the entry of the leveller, that is to say when k varies from 1 to x, and extends at least as far as the fifth roll from the entry of the leveller.
  • the radius/center-to-center spacing ratio R/E k is between 0.90 and 0.95 (limits inclusive).
  • This second zone lies between the fifth roll from the entry of the leveller and the (n ⁇ 4)th roll from the entry of the leveller, that is to say when x varies from 5 to n ⁇ 4.
  • a third zone lies between the (x+2)th roll from the entry of the leveller and the last roll of the leveller (the (n+1)th roll), that is to say when k varies from x+2 to n.
  • the radius/center-to-center spacing ratio R/E k is constant and between 0.70 and 0.80 (limits inclusive).
  • the leveller is again divided into three zones.
  • a first zone lies, as in the previous embodiments, between the first roll from the entry of the leveller and the (x+1)th roll from the entry of the leveller, that is to say when k varies from 1 to x, and extends at least as far as the fifth roll from the entry of the leveller.
  • the radius/centre-to-centre spacing ratio R/E k is between 0.90 and 0.95 (limits inclusive).
  • This second zone lies between the fifth roll from the entry of the leveller and the (n ⁇ 4)th roll from the entry of the leveller, that is to say when x varies from 5 to n ⁇ 4.
  • a third zone lies between the (x+2)th roll from the entry of the leveller and the last roll of the leveller (the (n+1)th roll), that is to say when k varies from x+2 to n.
  • the radius/centre-to-centre spacing ratio R/E k is constant and between 0.70 and 0.80 (limits inclusive).
  • the invention also relates to a method for levelling a metal strip, in which one of the levellers described above is used with a degree of plastic deformation of at least 60% but at most 90%.
  • the degree of plastic deformation of a metal strip is defined as being the thickness of the plastically deformed metal strip to the total thickness.
  • the degree of plastic deformation is less than 60%, it is no longer possible to remedy the flatness defects of the strip.
  • this degree of plastic deformation is greater than 90%, the metal strip becomes difficult to level and in this case it is also difficult to remedy the flatness defects of the strip.
  • the metal strip to be levelled may be made of steel, either carbon steel or stainless steel, coated with a metal coating, for example based on zinc, or with an organic coating.
  • a conventional leveller denoted by leveller X, comprising (k+1) rolls with k equal to 16, i.e. seventeen rolls, with a diameter of 57 mm and a constant center-to-center spacing E k of 30 mm (a leveller of the BRONX type), therefore having a constant radius/center-to-center spacing ratio R/E k of 0.95, was modified in order to obtain various levellers according to the invention, namely:
  • a steel strip 2 mm in thickness and 1000 mm in width was then made to run through each of these levellers A, B, C and X, applying either a degree of plastic deformation of 60% or 80%.
  • the steel in question was a steel of the THR1000 type, the yield strength R p0.2 of which was 900 MPa.
  • FIGS. 2 and 3 show a calculation curve of the residual curl of the levelled steel strip as a function of the exit clamping of the leveller for a degree of plastic deformation of 60% ( FIG. 2 ) and for a degree of plastic deformation of 80% ( FIG. 3 ).
  • leveller A is the leveller allowing the largest reductions in force and moment to be obtained, irrespective of the degree of plastic deformation.
  • this leveller is not necessarily the most reliable if it is desired to give the metal strip a perfectly zero curl, since, in particular when the degree of plastic deformation is 60%, the number of operating points is 1, whereas it is 9 in the case of leveller C.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Straightening Metal Sheet-Like Bodies (AREA)
  • Pinball Game Machines (AREA)
  • Feeding And Guiding Record Carriers (AREA)
  • Treatment Of Fiber Materials (AREA)
  • Controlling Rewinding, Feeding, Winding, Or Abnormalities Of Webs (AREA)
  • Rolling Contact Bearings (AREA)
  • Vehicle Body Suspensions (AREA)
  • Valve Device For Special Equipments (AREA)
  • Finger-Pressure Massage (AREA)
  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • Transition And Organic Metals Composition Catalysts For Addition Polymerization (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)
  • Heat Treatment Of Strip Materials And Filament Materials (AREA)
  • Earth Drilling (AREA)
  • Soil Working Implements (AREA)
US10/591,912 2004-03-10 2005-03-01 Roller leveller with variable center distance Expired - Fee Related US7617710B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR0402482A FR2867401B1 (fr) 2004-03-10 2004-03-10 Planeuse a entraxe variable
FR0402482 2004-03-10
PCT/FR2005/000482 WO2005097369A1 (fr) 2004-03-10 2005-03-01 Planeuse a entraxe variable

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US20070186607A1 US20070186607A1 (en) 2007-08-16
US7617710B2 true US7617710B2 (en) 2009-11-17

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US (1) US7617710B2 (ko)
EP (1) EP1725352B1 (ko)
JP (1) JP4657285B2 (ko)
KR (1) KR101030942B1 (ko)
CN (1) CN100425367C (ko)
AT (1) ATE401143T1 (ko)
BR (1) BRPI0508585B1 (ko)
CA (1) CA2558816C (ko)
DE (1) DE602005008207D1 (ko)
ES (1) ES2309748T3 (ko)
FR (1) FR2867401B1 (ko)
MX (1) MXPA06010322A (ko)
PL (1) PL1725352T3 (ko)
PT (1) PT1725352E (ko)
RU (1) RU2374021C2 (ko)
SI (1) SI1725352T1 (ko)
UA (1) UA89371C2 (ko)
WO (1) WO2005097369A1 (ko)
ZA (1) ZA200607315B (ko)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100058823A1 (en) * 2005-11-22 2010-03-11 Siemens Vai Metals Technologies Sas Method for levelling a flat product in strip or sheet form in a levelling machine with intermeshed rolls and levelling installation therefore

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103331338A (zh) * 2013-07-02 2013-10-02 无锡天惠塑机有限公司 准直式自动控制调直装置
BE1021399B1 (nl) * 2014-04-17 2015-11-16 Van Heyghen Staal Nv Een productiemethode voor een vlakke metaalplaat
CN104384246B (zh) * 2014-09-30 2017-07-28 巢湖广丰金属制品有限公司 一种带钢精细整形自动控制系统和方法
US10010918B2 (en) * 2016-10-05 2018-07-03 Allor Manufacturing Inc. Device and method for leveling a metal plate

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2334440A1 (fr) 1975-12-09 1977-07-08 Mesta Machine Co Machine et procede pour dresser des toles
US4635458A (en) * 1985-04-24 1987-01-13 Monarch Machine Tool Co. Leveling apparatus

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3312094A (en) * 1963-11-29 1967-04-04 Siegner Maschb G M B H Sheet leveler
JPS6261729A (ja) * 1985-09-11 1987-03-18 Hitachi Ltd 小径ロ−ル群複合矯正機
JPH07164051A (ja) * 1993-12-15 1995-06-27 Kawasaki Steel Corp ローラレベラの圧下量制御方法及びその実施に用いる制御装置
JP2000158045A (ja) * 1998-11-24 2000-06-13 Nisshin Steel Co Ltd 鋼帯の形状矯正方法
CN1193836C (zh) * 2001-10-19 2005-03-23 中国第二重型机械集团公司 板带材变辊距矫直机

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2334440A1 (fr) 1975-12-09 1977-07-08 Mesta Machine Co Machine et procede pour dresser des toles
US4635458A (en) * 1985-04-24 1987-01-13 Monarch Machine Tool Co. Leveling apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100058823A1 (en) * 2005-11-22 2010-03-11 Siemens Vai Metals Technologies Sas Method for levelling a flat product in strip or sheet form in a levelling machine with intermeshed rolls and levelling installation therefore
US8127580B2 (en) * 2005-11-22 2012-03-06 Siemens Vai Metals Technologies Sas Method for levelling a flat product in strip or sheet form in a levelling machine with intermeshed rolls and levelling installation therefore

Also Published As

Publication number Publication date
BRPI0508585B1 (pt) 2019-05-07
EP1725352B1 (fr) 2008-07-16
PL1725352T3 (pl) 2008-12-31
CN1942259A (zh) 2007-04-04
US20070186607A1 (en) 2007-08-16
CA2558816A1 (en) 2005-10-20
ATE401143T1 (de) 2008-08-15
JP4657285B2 (ja) 2011-03-23
FR2867401B1 (fr) 2006-04-21
EP1725352A1 (fr) 2006-11-29
CN100425367C (zh) 2008-10-15
UA89371C2 (ru) 2010-01-25
PT1725352E (pt) 2008-10-01
SI1725352T1 (sl) 2008-12-31
DE602005008207D1 (de) 2008-08-28
FR2867401A1 (fr) 2005-09-16
BRPI0508585A (pt) 2007-08-21
JP2007528298A (ja) 2007-10-11
ES2309748T3 (es) 2008-12-16
CA2558816C (en) 2011-07-26
MXPA06010322A (es) 2008-03-25
RU2006135638A (ru) 2008-04-20
KR20060126812A (ko) 2006-12-08
WO2005097369A1 (fr) 2005-10-20
ZA200607315B (en) 2008-04-30
RU2374021C2 (ru) 2009-11-27
KR101030942B1 (ko) 2011-04-28

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